/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.core.construction;



import com.bff.gaia.unified.sdk.annotations.Experimental;

import com.bff.gaia.unified.sdk.annotations.Experimental.Kind;

import com.bff.gaia.unified.sdk.coders.Coder;



import java.util.List;



/**

 * An interface that translates coders to components and back.

 *

 * <p>This interface is highly experimental, and incomplete. Coders must in the general case have

 * the capability to encode an additional payload, which is not currently supported. This exists as

 * a temporary measure.

 */

@Experimental(Kind.CORE_RUNNERS_ONLY)

public interface CoderTranslator<T extends Coder<?>> {

  /** Extract all component {@link Coder coders} within a coder. */

  List<? extends Coder<?>> getComponents(T from);



  /**

   * Returns the serialized payload that will be provided when deserializing this coder, if any. If

   * there is no payload, a byte array of length 0 should be returned.

   *

   * <p>The default implementation returns a byte array of length zero.

   */

  default byte[] getPayload(T from) {

    return new byte[0];

  }



  /** Create a {@link Coder} from its component {@link Coder coders}. */

  T fromComponents(List<Coder<?>> components, byte[] payload);

}